Known methods for measuring a first magnetic field and the temperature of a magneto-resistive transducer comprise:                the production, by the magneto-resistive transducer, of a measurement signal dependent on the intensity of the first magnetic field, this measurement signal also being dependent on the temperature of the magneto-resistive transducer,        the establishment of a measurement of the intensity of the first magnetic field on the basis of the measurement signal produced, and        the establishment of a measurement of the temperature of the magneto-resistive transducer.        
The measurement of the temperature of the magneto-resistive transducer is for example useful for temperature-compensating the measurement of the first magnetic field or the measurement of the current which generates this first magnetic field. It has been proposed in application US 2005/0077890 to use the same magneto-resistive transducer to measure both the first magnetic field and the temperature. In this document, the first magnetic field is generated by a current Im to be measured flowing in an electrical conductor placed in proximity to the magneto-resistive transducer. When the temperature of the magneto-resistive transducer has to be measured, the current Im is interrupted and then replaced with a current Ic whose characteristics are known. The measurement signal generated by the magneto-resistive transducer varies, for a given current Ic as a function of the temperature. Thus, by fixing the current Ic it is possible to measure the temperature with the aid of this magneto-resistive transducer.
This method is particularly advantageous since the same magneto-resistive transducer is used to measure the temperature and the first magnetic field.
However, measurement of the temperature makes it necessary to interrupt the current Im. But, when the current sensor described in US 2005/0077890 is used, for example, to measure the current in a phase of an electric motor, it is not possible to interrupt the current Im.
Prior art is also known from:                US2010/231213A1, and        HAN et Al: “Novel zero-drift detection method for highly sensitive GMR biochips”, IEEE Transactions on magnetics, IEEE Service center, New York, US, vol. 42, No. 10, 1 Oct. 2006.        